Irvine, Calif. A type of omega-3 fatty acid may slow the growth of two brain lesions that are hallmarks of Alzheimers disease, UC Irvine scientists have discovered. The finding suggests that diets rich in docosahexaenoic acid (DHA) can help prevent the development of Alzheimers disease later in life.
This study with genetically modified mice is the first to show that DHA, an omega-3 fatty acid, can slow the accumulation of tau, a protein that leads to the development of neurofibrillary tangles. Such tangles are one of two signature brain lesions of Alzheimers disease. DHA also was found to reduce levels of the protein beta amyloid, which can clump in the brain and form plaques, the other Alzheimers lesion.
Previous studies have shown that DHA may have therapeutic value for Alzheimers patients, but this research is among the first to show that it may delay the onset of the disease. DHA is found in fish, eggs, organ meats, micro-algae, fortified foods and food supplements.
We are greatly excited by these results, which show us that simple changes in diet can positively alter the way the brain works and lead to protection from Alzheimers disease pathology, said Frank LaFerla, professor of neurobiology and behavior and co-author of the study.
This research appears in the April 18 issue of The Journal of Neuroscience.
LaFerla and his research team studied the effects of DHA in mice bred to develop the plaques and tangles associated with Alzheimers disease. Mice in the control group were given food that mimics a typical American diet, with the ratio of omega-6 fatty acids to omega-3 fatty acids being 10:1. Studies indicate that a proper ratio is important to maintain health, with the ideal being 3:1 to 5:1. Typical Western diets contain unhealthy ratios ranging from 10:1 to 30:1. Omega-6 fatty acids are found in corn, peanut and sunflower oils.